MACHIAS, Maine (AP) -- Public health agencies and drug treatment centers nationwide are scrambling to battle an explosive increase in cases of hepatitis C, a scourge they believe stems at least in part from a surge in intravenous heroin use.

In Thursday, July 30, 2015 photo Ryan Kinsella is recovering from a long battle with hepatitis C. (AP Photo/Robert F. Bukaty)

In response, authorities are instituting or considering needle exchange programs but are often stymied by geography -- many cases are in rural areas -- and the cost of treatment in tight times.

In Washington County, at the nation's eastern edge, the rate of the acute form of hepatitis C last year was the highest in a state that was already more than triple the national average. The problem, health officials there agree, is spurred by the surge in the use of heroin and other injectable drugs and the sharing of needles to get high.

Ryan Kinsella's story is sadly typical. He was badly hurt in a rock climbing accident and became dependent on opioid painkillers several years ago. But when his prescriptions ran out, he sought drugs from the street, where he found heroin cheaper and easy to get, replacing one addiction for another. He's now recovering from hepatitis C.

"It's tough getting medical professionals to look at you as something that's not a junkie," said Kinsella, 33, who runs a bicycle shop in tiny Penobscot, next door in Hancock County. "There's a little bit of social stigma, and there's a little bit of `There's nothing we can do for you' that's hard to hear."

Maine is undergoing its worst outbreak of acute hepatitis C since it started to record cases in the 1990s. In Washington County, the rate is about 6 cases per 100,000 residents, well above the national rate of about 0.7 per 100,000.

But the problem is not limited to Maine, by far. It has afflicted other areas where heroin use is a growing concern, such as:

-- Springfield, Missouri, where the disease is on the rise and police have already confiscated more than five times the amount of heroin as in 2013.

-- Madison County, Indiana, which had 70 new cases of hepatitis C in 2013, followed by 130 in 2014, and where health officials expect current rates to at least match or surpass last year's. (Indiana's Scott County is also grappling with an HIV outbreak among injection drug users.)

-- Massachusetts, where cases of acute hepatitis C grew from 10 in 2009 to 174 in 2013.

-- Large swaths of Appalachia. Kentucky leads the nation in the rate of acute hepatitis C, with 5.1 cases for every 100,000 residents, more than seven times the national average, according to 2013 data from the Centers for Disease Control and Prevention.

Hepatitis C, which can result in liver failure, liver cancer and other serious complications, is the nation's most common blood-borne infection. About 3 million Americans are infected, according to federal statistics. It presents as either acute, or short-term, and chronic, which can last a lifetime. Both forms are most closely linked to needle-sharing, although hepatitis C is less commonly spread through unprotected sex or other contact with infected blood.

Nationwide, the number of cases of acute hepatitis C grew 273 percent from 2009 to 2013, the CDC reported in its most recently available statistics. Tracking similarly is heroin use; the CDC reported that the number of users nationwide rose nearly 150 percent from 2007 to 2013 and that use of the drug also more than doubled among ages 18 to 25 in the decade that ended in 2013.

More than 19,000 people died from hepatitis C in 2013, up from 16,235 in 2009, according to the CDC. Although the agency hasn't established a causal link between individual hepatitis C outbreaks and injected drug use, it notes that injected drug use is the primary risk factor for hepatitis C infection in this country.

Many local health agencies and health care providers have made the connection or are confident there is one, and are allowing users to turn in dirty syringes in exchange for clean ones. But many states disallow the practice and federal funding for it is banned.

Madison County, in central Indiana, won approval in June to run a needle-exchange program to fight the spread of hepatitis C among intravenous drug users. Clallam County, Washington, public health program manager Christina Hurst operates the local needle exchange program and calls it "one of the best interventions we have for this prevention," and a key tool to prevent dirty needles from being discarded in public.

A rise in acute hepatitis C, which nearly tripled in Washington between 2009 and 2013, is due to "most likely the needle sharing aspect of needle drug use," Hurst said.

Maine's Downeast AIDS Network opened the only needle exchange program in Washington County about a year ago in Machias, the county seat, one of six such programs in the mostly rural state.

The AIDS Resource Center of Wisconsin, which also provides services for people with hepatitis, says it collected more than 3 million needles in 2014, up from a million in 2010.

Last month, a law took effect in Ohio making it easier for health departments to establish needle exchanges. The state had more than 100 cases of acute hepatitis C last year and the previous year, up from single digits in 2005 and 2006.

In Franklin County, home to Columbus, the capital and the state's largest city, hepatitis C was diagnosed in 1,369 people last year, up from 719 in 2010. A decade ago, it had zero cases.

The costs of prevention and treatment often fall on public health agencies when many patients don't have insurance and can't pay. That can add up fast when just getting a diagnosis can be $19, said Scott Stokes, executive director of the Wisconsin AIDS center.

Rural regions like Washington County and parts of Appalachia and the Midwest struggle with drug problems because of poverty, job shortages and the difficulty of providing care in a vast area with few large population centers, said Kenney Miller, executive director of the Downeast AIDS Network.

The virus differs from hepatitis A, which is spread person-to-person or via contaminated food or water, and hepatitis B, which is transmitted by bodily fluids. There are vaccines for hepatitis A and B, unlike hepatitis C, for which there is none.

New treatments are available, but they're expensive and out of reach of most of the rural poor who make up the ranks of the infected. For instance, Harvoni, the leading drug to treat hepatitis C, costs more than $1,300 per pill.

Even so, the number of prescriptions filled for hepatitis C drugs more than doubled to a monthly average of 48,000 during the early part of 2015.

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